Rockets shoot off from a Ukrainian Grad multiple rocket launcher towards the position of pro-Russian militants in Donetsk region on Thursday. (ANATOLII STEPANOV/AFP/Getty Images)

WASHINGTON — NATO members will set their 2015 slate of reassurance measures — actions meant to bolster Eastern European defenses — and debate the alliance’s post-Afghanistan path at next month’s summit in Wales, a senior Pentagon official said.

All 28 member countries have pledged to participate in the measures, including air policing and surveillance flights, in the wake of Russia's February invasion of Crimea and continued massing of troops near Ukraine's eastern border.

Because NATO’s current agreement on reassurance measures expires at the end of the year, alliance members will look to firm up new measures for 2015 at the summit, said Derek Chollet, assistant defense secretary for international security affairs.

"What we're trying to do is use this summit beyond the just symbolic effort to show unity, but to try to get NATO to sign up to some concrete initiatives that will position it for the future," Chollet said.

A key enabler of the reassurance plans next year is the $1 billion European Reassurance Initiative, which the Obama administration has proposed as part of the Pentagon's 2015 budget.

The US intends to use the $1 billion – which Congress must still approve – to fund exercises, more rotations of US forces throughout Europe, infrastructure projects for partners and possibly the pre-positioning of equipment.

The Initiative "shows the United States' enduring commitment to the security of Europe," NATO Secretary General Anders Fogh Rasmussen said in a July 7 speech at the Atlantic Council think tank in Washington. "Now other allies need to strengthen their commitment."

The US also plans to use the upcoming summit "as a way to galvanize some of our European partners to ensure that they're spending the right kind of resources on defense," Chollet said.

After more than a decade of fighting in Afghanistan, many NATO countries have been cutting defense spending. US leaders have been encouraging alliance members to invest more strategically as budgets tighten.

A number of Eastern European nations, including Poland, Romania and Latvia, have pledged to increase defense spending in the wake of Russia's recent military actions in and around Ukraine.

Last month, the British Prime Minister David Cameron pledged to spend £1.1 billion (US $1.8 billion) on defense equipment.

London is "very actively leading the charge, along with us, to get more countries to sign up for more," Chollet said.

Another focus of the summit will be looking for ways that NATO can improve coordination among its members during capacity-building efforts with key partners, Chollet said.

There have been challenges when conducting defense capacity-building missions in countries, such as Libya, where a number of countries are working on individual efforts in this area.

"We're coordinating as best we can, but it's not as well-coordinated as it would be if we were part of an organization doing it," Chollet said. "It's all sort of ad hoc."

NATO's organizing capacity could make these partner-building efforts more effective, he said.